Organic electroluminescent (EL) displays are known as display devices that use current-driven light-emitting elements. Due to such advantages as having excellent viewing angle characteristics and low power consumption, organic EL displays have gained much attention.
In organic EL display devices, organic EL elements included in pixels are normally arranged in a matrix. In particular, in an active-matrix organic EL display, it is possible to cause an organic EL element to emit light until the next scanning (selection), and thus display luminance does not decrease even if duty ratio increases. Therefore, since driving with low voltage is possible, reduction of power consumption becomes possible. Unfortunately, in the active-matrix organic EL display device, due to variation in the characteristics of the drive transistors and organic EL elements, the luminance of the organic EL elements are different among the respective pixels even when the same luminance signal is supplied, and thus there is the disadvantage of the occurrence of what is called luminance unevenness.
As a method of correcting luminance unevenness in a conventional organic EL display, a method which compensates for non-uniformity of characteristics of each pixel by correcting the luminance signal using correction data stored in advance in a memory.
For example, Patent Literature (PTL) 1 discloses an organic EL display device manufacturing method used in a display panel having pixels each including an organic EL element and a drive transistor. The organic EL display device manufacturing method includes obtaining the representative current-voltage characteristic, the luminance-current characteristic of respective segment regions, and the luminance-voltage characteristic of the respective pixels, and obtaining, for each pixel, correction data by which the current-voltage characteristic of the respective pixels obtained from the obtained characteristics can be made to equal the representative current-voltage characteristic. Accordingly, highly-accurate correction data can be obtained, and thus unevenness in luminance deterioration attributed to service life can be suppressed.